1949-2016年我国粮食主产区旱灾变化趋势分析

Analysis on the trend of drought in main grain producing areas in China from 1949 to 2016

关键词:  粮食主产区  旱灾  受灾率  成灾率  趋势

Key words:  main grain producing area  drought  the ratio of affected area  the ratio of suffering area  trend

摘要:

采用趋势线法、Mann-Kendall（M-K）趋势检验法及Mann-Kendall（M-K）突变检验法对1949-2016年我国粮食主产区旱灾变化趋势进行分析，以期为降低粮食主产区旱灾风险及灾害损失的措施制定提供理论依据。结果表明：1）除江苏省外，干旱发生率均高于60%，干旱受灾率和成灾率的变异系数均在50%以上。2）东北地区各省干旱受灾率和成灾率均呈现增加趋势且通过M-K趋势检验，增加趋势显著；长江流域的湖北和四川省干旱受灾率呈增加趋势，江西和湖南省干旱受灾率呈减少趋势，但均未通过M-K趋势检验，变化趋势不显著；上述长江流域四省干旱成灾率均呈增加趋势，但只有湖北和四川省通过M-K趋势检验，增加趋势显著；黄淮海地区除江苏省干旱受灾率呈微弱线性增加趋势外，其他各省干旱受灾率均呈减少趋势，但只有安徽省通过M-K趋势检验，表现出显著的减少趋势；黄淮海五省成灾率均呈增加趋势，但只有河北和江苏省通过M-K趋势检验，增加趋势显著。3）M-K突变检验结果表明，安徽省旱灾受灾率变化突变点为2002年，之后呈减少趋势；东北三省及内蒙古自治区干旱受灾率变化突变点分别为1977、1970、1983和1977年，之后干旱受灾率呈增加趋势；各省区干旱成灾率突变点如下：东北地区的黑龙江、吉林和辽宁省及内蒙古自治区分别为1988、1977、1981和1984年，黄淮海地区的河北和江苏省分别为1961和1978年，长江中下游地区的湖北和四川省分别为1986和1975年，各省区干旱成灾率在突变点之后均呈增加趋势。综上，粮食主产区干旱灾害发生率普遍较高且年际变化大，东北地区旱灾影响范围、规模以及致灾程度均呈显著增加趋势；黄淮海地区的河北和江苏省以及长江中下游地区的湖北和四川省虽然干旱影响范围和规模没有表现出显著的变化趋势，但是旱灾的致灾程度却表现出显著的增加趋势；干旱受灾率显著期普遍发生在2000年后；干旱成灾率增加趋势显著期普遍发生在20世纪90年代末-2010年前后。

Abstract:

The trend of drought was analyzed in China's major grain producing areas during the period from 1949 to 2016 using the trend line method and Mann-Kendall non-parametric test method.The objective was to provide a theoretical basis for reducing drought risk and disaster losses in major grain producing areas.The results showed that:1) The incidence of drought was higher than 60% except for Jiangsu Province.The variation coefficient of drought disasters was higher than 50%.2) The M-K trend test results show that the ratio of affected area was increasing in Heilongjiang,Inner Mongolia,Jilin and Liaoning provinces,but Anhui Province had a significant decreasing trend.The ratio of suffering area was increasing in Heilongjiang,Inner Mongolia,Jilin,Liaoning,Hebei,Jiangsu,Hubei and Sichuan provinces.The trend was not significant in the other provinces of main grain producing areas.3) The results of M-K mutation test also showed that the mutation point of the ratio of affected area in Anhui Province was in 2002,and it showed a decreasing trend after 2002.The mutation point was respectively 1977,1970,1983 and 1977 in Heilongjiang,Jilin,Liaoning and Inner Mongolia.It showed an increasing trend thereafter,and the ratio of affected area increased significantly since 2000.The mutation point of the ratio of suffering area was respectively 1988,1977,1981,1984,1961,1978,1986 and 1975 in Heilongjiang,Jilin,Liaoning,Inner Mongolia,Hebei,Jiangsu,Hubei and Sichuan provinces.The ratio of suffering area increased drought rate significantly from the late 1990s to 2010.